The present invention relates generally to internal combustion engines, and more particularly to a structural system which permits the engine fuel injector plunger piston to in effect control actuation of one or more of the engine exhaust valves so as to achieve compression braking of the engine.
In order to achieve compression braking, it is usually required to incorporate into the structural operating system various auxiliary operating components, such as, for example, pumps or other similar pumping or actuating mechanisms in order to appropriately control the engine exhaust valve which will be actuated in order to achieve the compression braking mode of the engine. The incorporation of such auxiliary actuating components into the structural operating system of the engine, however, in order to achieve the compression braking operating mode of the engine, adds substantially to the overall engine costs.
The present invention is directed to overcome on or more of the problems as set forth above.
The foregoing need is achieved in accordance with the principles and teachings of the present invention through the provision of a new and improved internal combustion engine fueling and compression braking hydraulically actuated, electronically controlled unit injector (HEUI) mechanism or system which comprises an engine cylinder; a fuel injector for injecting fuel into the engine cylinder such that the fuel can be combusted; a piston for causing pressurization of the fuel to be delivered to the fuel injector; an exhaust valve operatively associated with the engine cylinder for controlling the exhaust of gaseous products from the engine cylinder; an exhaust valve rocker arm operatively connected to the exhaust valve so as to control the opening of the exhaust valve when the exhaust of gaseous products from the engine cylinder is desired; a compression brake actuating system for operatively interconnecting the piston to the exhaust valve rocker arm; and a control system operatively connected to the compression brake actuating system for alternatively disposing the compression brake actuating system in two different operative modes wherein when the compression brake actuating system is disposed in a first one of the two different operative modes, the compression brake actuating system is operatively disconnected from the piston such that movement of the piston causes normal engine fuel injection to occur, and wherein when the compression brake actuating system is disposed in a second one of the two different operative modes, the compression brake actuating system is operatively connected to the piston such that movement of the piston causes the compression brake actuating system to actuate the exhaust valve rocker arm so as to in turn actuate the exhaust valve such that compression braking can occur.